a prism, or “ spectrometer ” , splits visible light
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A prism, or “ spectrometer ” , splits visible light ‘ white light ’ up into its different components. The FULL Electromagnetic Spectrum. What is doing the “ waving ” ?. An EM wave is a moving self-generating combination of electric and magnetic fields - PowerPoint PPT PresentationTRANSCRIPT
A prism, or “spectrometer”, splits visible light ‘white light’ up into its different components
The FULL Electromagnetic
Spectrum
What is doing the “waving”?
An EM wave is a moving self-generating combinationof electric and magnetic fields
Light is like water waves in that it has wavelength and frequency but unlike them in that it needs no medium to move through
direction of propagation of the EM wave
Light As A Particle
Photo-electric effect
E = hc /
What kinds of things emit light?Hot objects – blackbody radiation
– Higher the temperature, the more energy emitted and higher the frequency of light
Examples:
cool dust and gas at 10-1000 K: infrared
surface of sun at 6000 K: visible light
hot gas in corona of sun at 1,000,000 K: X-rays
Atoms – create spectral lines – every atom has its own “spectral signature”
Light is also a particle - photon
Light travels in “packets” of energy, or quanta
E = (h * C) / WavlengthEnergy = constant divided by wavelength
Shorter Wavelength More energy
Light acts like a particle when interacting with matter – absorbed and radiated like particles
Light acts like a wave when traveling, can be bent, reflected, or interfered with, like water waves
Three Kinds of Spectra